Tropical Rainforests Flashcards
What is an ecosystem?
A unit that contains all the biotic and abiotic parts in an area
What are biotic factors?
Living e.g. insects bacteria
What are abiotic factors?
Non living e.g. sunlight and heat
What is a biome?
A global scale ecosystem
What is a biosphere?
All the living organisms in the world and their physical environment
What are the two main sources of nutrients in an ecosystem?
Rainwater
Weathering of rocks
Where are TRFs found?
Broad belt close to the equator
From South America -> west Africa -> Southeast Asia + Australia
What is the climate of a TRF?
Equatorial climate
High temperatures
High rainfall
What are plants and animals like in TRFs?
Highest level of biodiversity in the world
Birds live in canopy
Mammals are adapted to trees
What are people like in TRFs?
Traditional tribes gather what they need to survive - sustainable
However people are exploiting rainforests
What are soils like in TRFs?
Not very fertile
Nutrients concentrated in top soil
Shall roots
Leeching removes nutrients from the top soil
What is the rainfall like in TRFs?
Distinct wet seasons
Swells local rivers + soaks into soil causing leeching
What resources are species competing for in tropical rainforests?
Light
Space
Nutrients
Water
What are Lianas and how are they adapted?
Vines that have roots in the ground
They climb trees to reach sunlight
What are buttress roots and how are they adapted?
Long roots allow trees to soak up all of the possible nutrients from the soil
What are drip tips and how are they adapted?
Leaves with pointy tips
Allows water to drip off without damaging their leaves
How is a three toes sloth adapted?
Extra vertebrae to be able to run
Can swim in floods
Grown green algae in fur to camouflage
What are socio-economic values of rainforests + examples?
Resources - timber
Goods - cocoa and sugar
Medicine - 25% of medicine comes from plants in rainforests
Indigenous tribes - Jakuna
Energy - hydroelectric pepper
Employment - guides
What is the environmental value of rainforests?
Water - 20% worlds comes from rainforests
Biodiversity - 50% of the worlds plants exist in rainforests
Climate - carbon sink + 28% of worlds oxygen generated
Soil erosion - roots hold tropical soil together
Where are nutrients mainly stored in TRFs?
Biomass
How many different species of plants and animals are in the amazon?
15 million
What are the threats facing biodiversity?
Slash and burn agriculture
Mining and pollution of water
Development of roads and selltlemetns
Unsustainable timber harvesting
What are the problems of biodiversity declining?
Knock on effects on the ecosystem
Indigenous tribes are unable to survive in rainforests
Plant and animal species may become extinct
Important medical plants may become extinct
What are the causes of deforestation?
Farming
Logging
Mineral extraction
Energy development
Road building
Settlement + population growth
What are the 3 types of farming?
Cattle
Crops (subsistence)
Crops (commercial)
What is the issue with commercial ranching?
Leading cause of deforestation in Brazilian amazon
Destruction of nutrient cycle
Land can only sustain herds for short periods of time
What is the issue with subsistence farming?
3 million landless people in Brazil
Farmers stay on the land and attempt to farm
The land quickly becomes exhausted
What is the issue with commercial farming?
Large plantations have been made
Crops like palm oil, sugar cane and soybeans are grown
Soil can only sustain for a short period of time
What is the issue with logging?
Cutting down trees like mahogany and teak
Accounts for 3% of deforestation
Can be sued for furniture fuel and charcoal
What is the issue with mining?
50,000 hectares in 2016 were used
Particularly damaging as the land needs to be cleared and the top soil removed
What is the issue with energy development?
Constructing dams and resistors floods large areas of forest
This damages the rainforest + causes the water to become acidic
Belo monte has flooded more than 40,500 hectares of rainforest
What is the issue with road building?
Large amounts of forest are cleared
Which opens up accessibility to people so there is more deforestation
What is the issue with population growth?
Atttracting employees as there are economic opportunities
This leads to migration - so more deforestation
How can local climate change affect people?
Rainfall patterns can significantly change leading to further vegetation loss
Can cause people to move
What is the issue with declining soil erosion and fertility?
Nearby rivers get silted up, increasing flood risk
More deforestation occurs
What are the issues with river pollution?
Local governments may have to incest in increased medical care
Mercury being released is irreversible
May cause a breakdown of the ecosystem
What is the issue with the decline of indigenous tribes?
Once indigenous tribes are disturbed, their culture ad way of life are changed forever
Knowledge is lost
What is the issue with biodiversity loss?
Species becoming extinct is irreversible, breakdown of foodchains
What are small scale forestry sustainable techniques?
Selective logging
Agroforestry
Replanting
What is selective logging?
Only felling fully grown trees - less valuable ecologically
Younger trees provide protection from soil erosion
Can’t be felled until they are at least 30 years old
What is agroforestry and the benefits?
Growing crops and trees together
Can control runoff and erosion, reducing losses of water, soil and organic matter
What is replanting?
Collecting seeds from remaining patches of the original forest and planting them into areas which have been deforested
When was the international timber agreement and what is it?
2006
Restricts trade in tropical rainforest hardwoods - makes them more difficult to sell
What is debt reduction in TRFs?
HICs are allowing LICs to pay off debt they owe by putting the money into protecting their rainforests
What is ecotourism?
Tourism that works with rather than against the environment
Profit stays in the local area
